package com.heima.gateway.filter;

import com.heima.gateway.utils.AppJwtUtil;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/*
全局过滤器，校验token是否有效
 */
@Component
@Slf4j
public class AuthorizeFilter implements GlobalFilter, Ordered {
    /**
     * 执行过滤的方法
     * @param exchange 交换机，可以获取请求和响应对象
     * @param chain 过滤器链
     * @return
     */
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        //1.获取request与response
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
        //2.判断是否是登录接口
        if (request.getURI().getPath().contains("/login")){
            log.info("登录接口");
            return chain.filter(exchange);//chain.filter(exchange)代表放行
        }
        //3.判断token是否为空
        String token = request.getHeaders().getFirst("token");
        if (StringUtils.isEmpty(token)){
            log.error("token为空");
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();//response.setComplete()代表终止请求的意思
        }
        //4.判断token是否正确
        Claims claimsBody = AppJwtUtil.getClaimsBody(token);

        int result = AppJwtUtil.verifyToken(claimsBody);

        if (result==1||result==2){
            log.error("token解析失败");
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();//response.setComplete()代表终止请求的意思
        }
        //5.放行
        return chain.filter(exchange);
    }

    /**
     * 过滤的执行的优先级，返回值越小优先级越高
     */
    @Override
    public int getOrder() {
        return 0;
    }
}
